Method and apparatus for ripping and polishing wire drawing dies



March 29, 1949 G. GARGANU 2,465,867 METHOD AND APPARATUS FOR RIPPING AND POLISHING WIRE DRAWING DIES Filed se a. 28, 1945 INVENTEIR. wfPP/ 64P64/v0,

Patented Mar. 29, 1949 METHOD AND APPARATUS FOR RIPPIN G AND POLISHING WIRE DRAWING DIES Guiseppl Gargano, New Haven, Conn., assignor to The American Steel and Wire Company of New Jersey, a corporation of New Jersey Application September 28, 1945, Serial No. 619,157

3 Claims.

The present invention relates to an improved method and means for ripping and polishing the holes of dies. While not limited thereto, the invention is peculiarly well suited for ripping and polishing the holes of wire drawing dies, in one continuous operation.

It is well known to those skilled in the art that wire drawing dies and the like require precision ripping, lapping, or polishing. Heretofore the usual practice has been to accomplish the ripping and polishing in two separate operations.

The term ripping," as understood by those skilled in the art, refers to the cutting of the hole in the die and the forming of it into the required general outline as viewed in longitudinal section. Those skilled in the art are also aware that the hole in a wire drawing die includes an entrance portion, a hearing or working portion, and a relief portion. The entrance and relief portions usually flare outwardly in opposite directions, and the working portion between them is usually substantially cylindrical or may have a very slight taper.

Heretofore it has been the common practice to first rip the hole in the die by reciprocating a; toofthrough the die opening so as to substantially shape the die hole to the desired contour viewed in longitudinal section, and to remove the die and subject it to a separate lapping operation to polish the hole. During both the ripping and polishing operations it has been conventional practice to use an abrasive such as diamond dust, emery dust, carborundum, or the like.

Prior to my invention it has been generally regarded as essential to carry out ripping and polishing operations in two separate and distinct stages, frequently using separate tools, one for ripping and another for polishing. Under my invention, as will appear more fully hereinafter, I accomplish both the ripping and polishing of the annular wall of the hole in the die in one continuous operation, usually by the use of the same abrading tool.

For a more complete understanding of the invention, reference should be made to the following description, the appended claims, and the accompanying drawings, in which:

Figure 1 is a front elevation of a portion of a machine well suited for carrying out my improved method.

Figure 2 is a longitudinal detail section illustrating an antifriction mounting for the die support.

Referring to the drawings. illustrating a pre- 2 ferred means for making the herein claimed invention available, I provide a machine In including a fixed base [2 in which is mounted a plurality of duplicate vertically movable die holder supports one of which is shown at l4. At the top of each support is an axial shank to which is secured the inner race of a ball bearing l6. Any other freely rotatable bearing could be used, but a ball or roller bearing is preferable. Mounted on the outer race member of the bearing is is a die holder l8 which is recessed at the top, as shown, to receive a die 20 to be conditioned, the periphery of the die making a slide or press fit with the annular wall of the recess.

Each support 14 is arranged to be vertically adjusted by means of a pin 22 which is rigidly attached to the support 14 and projects through a guide slot 23. The pin 22 rests on a lug 24 formed on a sleeve 26 which is caused to move up or down on a stationary screw 28 as a result of the rotation of a threaded thumb nut 30 as the latter turns on the screw 28. The purpose of the vertical adjustment of the support It and parts carried thereby is to move the die being ripped or polished into position for proper coaction with the ro ating reciprocating tool 32.

The ripping tool 32, such as usually used for ripping holes in wire drawing dies, is securely held by a suitable chuck carried by a revolving spindle 38 driven by a pulley 38 secured to the spindle. The assembly comprising the ripping tool, chuck, spindle, and pulley is revolved at a high rate of speed by means of a belt 40 reeved about a pulley 42 carried by a shaft 44. The shaft 44 is revolved by a pulley is driven by a belt 48 trained around a pulley 50 secured to the armature shaft of a motor 52.

While the ripping pin 32 is being revolved at a high rate of speed, which is necessary to rip a hole in a wire drawing die, the movable subframe 54 in which the spindle 36 is supported and carried, is caused to reciprocate up and down, the sub-frame 54 being mounted on vertical guide rods one of which is shown at 56. The lower end of each rod 56 rests on an eccentric 58 secured to a revolving shaft 60; The shaft 60 is revolved by means of a pulley 62 rigidly attached to the shaft 60 through the belt 64, and the pulley 66 which is rigidly attached to the above mentioned shaft 44. Thus as the motor drives shaft 60 at a high rate of speed, the eccentrics 58 thereon in turn cause a rapid vertical vibration of the rods 58, thus imparting a area of the wall of the hole in the die while the tool is being reciprocated lengthwise through the hole. Because the die is mounted on a support II which is freely rotatable, for example, on an anti-friction ball 'or roller bearing, the rotating action of the pin-like abrading tool on the wall of the die hole imparts a torque to the die, cau'sing it to rotate, this rotating movement also being transmitted by friction to th rotating die holder It. In practice, the ripping and polishing tool 32 may be placed slightly eccentric to the axis of the hole, which is preferably coincident with the axis of rotation of the support it and holder it. Thus the rotating abrading tool will constitute a friction drive, turning the die and the rotatable support on which it is mounted,

although the tool 32 charged with the abrasive substance may make a slipping contact with the wall of th die hole.

In the practice of my method, I continue the operation only until the abrasive action of the tool upon the wall of the die hole ceases to rotate the die and its holder ll. Thus an operator, by observing when the die stops rotating, is given an emphatic visual indication that the ripping and polishing operation has been completed. As soon as the die stops rotating, the spindle is stopped and the die is removed, the same having been thus both ripped and polished in one continuous operation, as distinguished from the two separate operations heretofore generally thought necessary by those skilled in the art.

Having thus described the invention, what I claim as new and desire to secure by Letters Patent is set forth in the following claims.

I claim:

1. The herein described method of ripping and polishing a hole in a die in one continuous operation, which comprises supporting the die with freedom for rotation, causing a rotating tool charged with an abrasive to reciprocate in contact with a restricted area of the wall oi the hole in the die and thus rotate said die, and continuing the operation only until the abrasive action of the tool upon the wall of the die hole ceases to rotate the die.

2. The herein described method 0! rippinl and polishing the hole of the wire drawing die in one continuous operation, which comprises supporting the die with freedom for rotation about an axis coincident with the die hole, causing a rotating pin-like tool charged with an abrasive to coact with a restricted area of the wall oi the hole in the die at a region eccentric to said axis while reciprocating the tool lengthwise within said hole, the rotation of said tool imparting a torque to the die eifective to rotate the latter, continuing the resulting ripping and polishing operation of the tool only until the abrasive action thereof upon the wall of the die hole ceases to rotate the die, and then withdrawing the tool and removing the die from its rotary support. 3. Apparatus for ripping and polishing the hole in a die in one continuous operation comprising a rotating pin-like tool, means for reciprocating the tool, a platform on which a die to be acted upon by said tool is mounted, said platform having a recessed top for receiving said die, a vertically movable support shaft for said platform having an axial shank around its upper end, said platform being mounted for rotation around said axial shank, said platform being rotated around said axial shank solely by the torqueexerted by said tool upon the wall of the hole in the 'die.

GUISEPPI GARGANO.

REFERENCES crrEn The following references are of record in the file of this patent:

UNITED STATES PATENTS Hanemann Nov. 6, 1945 

